Science & Studies: The Science of Grains
What is celiac disease?
Celiac disease is an inherited autoimmune disorder which, in the presence of gluten, causes the small intestine to become inflamed and lose its ability to absorb nutrients from food. Additionally, a growing number of people experience celiac-like symptoms, where they don't have the disease but seem to suffer from a gluten intolerance which makes them unable to digest gluten properly. Gluten is found in foods containing wheat, barley and rye and wheat-related grains such as einkorn, kamut and spelt. In addition to the gastrointestinal problems, the inability to absorb nutrients causes those with celiac disease to suffer from other disorders such as anemia, fatigue, osteoporosis, infertility and weight loss.
Celiac disease is estimated to affect less than one percent of the U.S. population; however, approximately 95% of those cases remain undiagnosed. According to the Celiac Disease Center at the University of Chicago, celiac disease is one of the most misdiagnosed and under-diagnosed conditions in this country. In fact, it can take as many as ten years for a patient to be diagnosed with this condition.
Do I need to follow a gluten-free diet?
Following a gluten-free diet is a necessity for those affected by celiac disease or for those who are gluten intolerant. However, some theories have been put forward suggesting gluten-free diets may also aid in the treatment of disorders ranging from autism and multiple sclerosis to attention deficit disorder. While many consumers believe these theories, there is almost no scientific evidence to support the use of gluten-free diets for situations other than celiac disease or gluten intolerance.
In fact, the science maintains gluten-free diets offer no benefits to those who do not suffer from celiac disease or gluten intolerance and may present some risks. Many gluten-free products are quite expensive, are low in dietary fiber and whole grain, may not be fortified with folic acid and may lack other important nutrients derived from grain-based foods.
For those who do suffer from celiac disease, there are gluten-free whole grains available. Corn, rice and quinoa, for example, will help provide necessary fiber and antioxidants to the diet. See below for a complete list of gluten-free grains.
What is glycemic index?
Glycemic index measures foods based on how they impact blood sugar levels thus impacting insulin production. While a number of foods have been identified as having a high glycemic index, the most common are carbohydrates including grain foods.
How does the glycemic index work?
Many foods that are high in carbohydrates both simple and complex score high on the glycemic index regardless of their calorie content or nutritional value. Furthermore, ranking foods solely by their glycemic index can lead to distorted nutrition recommendations. For example, a Snickers bar rates lower on the glycemic index (41) than oatmeal (48) or whole wheat bread (68). Avoidance of foods with a high glycemic index eliminates foods with valuable vitamins and nutrients.
Should I follow the glycemic index?
The utility of the glycemic index and glycemic load (GL) (which is defined as GI times grams of carbohydrate) with regard to health and weight control is overstated and simply not backed by a majority of the published research. In fact, most of the large-scale population studies fail to show any link between glycemic index or glycemic load and diseases such as diabetes and cancer. Even in studies showing an association between glycemic index/load and disease risk, the association may be eliminated by increasing dietary cereal fiber which comes from grain-based foods.
Some proponents of GI/GL suggest that low GI foods/GL diets can be useful for weight control. However, there are several studies that actually show the opposite occurs. At the very least, no major American health/medical organization has endorsed the use of glycemic index or glycemic load because the science is not strong enough to support their use.